(2 of ) The Schaefer family of Rocklin, including Herman and his granddaughters Brooke, in light blue and Morgan, bundled up against the cold temperatures at Bodega Bay's Doran Beach, Wednesday July 21 2010. KENT PORTER/ PD

Santa Rosa's highs 4 degrees cooler for season so far -- and it's likely to continue

Temperatures in Santa Rosa have been 4 degrees colder, on average, compared with the daily highs over the past 30 years from late May to this point in the summer.

On a typical day this summer, Santa Rosa has peaked at 76 degrees, according to Press Democrat records from May 21 through Tuesday. Over the past 30 years, daily highs have averaged 80 degrees during that same period.

Case in point, Wednesday's high in Santa Rosa was 75 degrees.

The summer season didn't get off to a great start. There were the rains in late May. And lingering fog on many days has forced some residents to light morning fires, turn on their heaters or keep their fleece close, at least until the sun finally breaks through.

"It's hella cold," said Steve Anderson, meteorologist for the National Weather Service in Monterey.

The lack of serious local heat this summer may seem amplified because of extreme heat waves rocking much of the country and other parts of the world.

While the East Coast has baked in record-setting highs, the West Coast is awash in still-green tomatoes.

Some are contacting nurseries for advice.

"A lot of people planted early and either lost their plants or they got awful because of the weather," said Kris Kapa, employee at Harmony Farm Supply nursery in Graton. "Most people are saying 'Why does my plant look so crummy?' "

It's just not warm enough yet to produce tomatoes or turn what's there red.

"They're just poking along," she said.

Anderson blamed a baggy pressure trough that has been hanging low over the West Coast, keeping out the warmer air and sucking in the cool marine air.

"It's persistent," Anderson said. "We've had this high pressure in the central U.S. for the longest time, too. The weather systems aren't moving very well."

In the short run, local temperatures should be heating up by the end of the week and for the weekend. Temperatures are predicted to rise into the mid-80s.

But apparently it won't last long.

"There'll be another trough of low pressure next week," Anderson said.

While summer fog is common in these parts, usually the region has had at least a few major strings of hot days by this time.

This summer, only two days have hit 90 degrees or above in Santa Rosa, with the highest temperature so far reaching 92 on June 27, according to Press Democrat statistics.

Other recent summers also have had cooler-than-average days, according to the National Weather Service.

For June and July to date this year, the average in Santa Rosa has been 78 degrees. In 2004 and 2005, the average for those months was 79 degrees. In 1998 and 1999, it was 77 degrees.

Anderson said the below-80 days might be something West Coasters should get used to, as climatologists point toward global warming.

"Even though places will be warmer, along the immediate coastal area it will be cooler because of increased offshore flow due to warmer inland temperatures," Anderson said.

What about those tomatoes?

Kapa suggested the best plan is to be patient and don't overwater.

"We have a bunch planted out here, 30 varieties. We hardly have any ripe ones at all."